public override void Execute()
{
var television = new Television();
Assert.IsType <TelevisionOffState>(television.State);
Assert.False(television.Powered);
Assert.Null(television.Volume);
Assert.Null(television.Muted);
television.LowerVolume();
// Nothing should changes when the television is off.
Assert.IsType <TelevisionOffState>(television.State);
Assert.False(television.Powered);
Assert.Null(television.Volume);
Assert.Null(television.Muted);
television.IncreaseVolume();
Assert.IsType <TelevisionOffState>(television.State);
Assert.False(television.Powered);
Assert.Null(television.Volume);
Assert.Null(television.Muted);
television.ToggleMute();
Assert.IsType <TelevisionOffState>(television.State);
Assert.False(television.Powered);
Assert.Null(television.Volume);
Assert.Null(television.Muted);
// Let's power it up.
television.TogglePower();
Assert.IsType <TelevisionOnState>(television.State);
Assert.True(television.Powered);
Assert.Equal(2, television.Volume);
Assert.False(television.Muted);
television.LowerVolume();
television.LowerVolume();
television.LowerVolume();
Assert.IsType <TelevisionOnState>(television.State);
Assert.True(television.Powered);
Assert.Equal(0, television.Volume);
Assert.False(television.Muted);
television.IncreaseVolume();
television.IncreaseVolume();
television.IncreaseVolume();
Assert.IsType <TelevisionOnState>(television.State);
Assert.True(television.Powered);
Assert.Equal(3, television.Volume);
Assert.False(television.Muted);
television.ToggleMute();
Assert.IsType <TelevisionMutedState>(television.State);
Assert.True(television.Powered);
Assert.Equal(3, television.Volume);
Assert.True(television.Muted);
television.IncreaseVolume();
Assert.IsType <TelevisionOnState>(television.State);
Assert.True(television.Powered);
Assert.Equal(4, television.Volume);
Assert.False(television.Muted);
television.ToggleMute();
television.ToggleMute();
Assert.IsType <TelevisionOnState>(television.State);
Assert.True(television.Powered);
Assert.Equal(4, television.Volume);
Assert.False(television.Muted);
television.TogglePower();
Assert.IsType <TelevisionOffState>(television.State);
Assert.False(television.Powered);
Assert.Null(television.Volume);
Assert.Null(television.Muted);
}
